CVA Vibration Standards & Safety 2

Question 1

Under ISO 10816-3 / ISO 20816-3, which evaluation zone describes vibration considered acceptable for unrestricted long-term operation?

Accepted Answer

Zone B

Answer

Zone B covers machines considered acceptable for unrestricted long-term operation, while Zone A is typical of newly commissioned machines.

Question 2

A machine's vibration is in Zone C of ISO 10816-3. What does that classification generally mean?

Accepted Answer

Operation is unsatisfactory for long-term continuous use but may continue for a limited period until remedial action

Answer

Zone C indicates the machine can run for a limited time but should be scheduled for corrective action.

Question 3

ISO 10816-3 recommends that the ALARM limit for a machine should normally NOT exceed approximately what value?

Accepted Answer

1.25 times the upper limit of Zone B

Answer

The standard suggests alarm settings around baseline plus 25% of the Zone B upper limit, generally not exceeding 1.25 times the B/C boundary.

Question 4

Which measurement quantity and frequency range does ISO 10816-3 use for evaluating broadband casing vibration on most industrial machines?

Accepted Answer

RMS velocity, typically 10 Hz to 1,000 Hz

Answer

ISO 10816-3 evaluates broadband RMS velocity, usually over 10-1,000 Hz (2-1,000 Hz for slower machines).

Question 5

In ISO 10816-3, machines are separated into Group 1 and Group 2 mainly according to what characteristic?

Accepted Answer

Rated power or shaft height

Answer

Group 1 covers large machines (above 300 kW or shaft height of 315 mm or more) and Group 2 covers medium machines (15-300 kW).

CVA - Certified Vibration Analyst Practice Test